mem: use general flags in page table manager

src/memory/mod.rs

@@ -3,6 +3,7 @@ mod pagetable;
 mod page;
 
 use crate::multiboot::MultibootTagMmap;
+use pagetable::flags::*;
 
 static PAGE_SIZE: usize = 4096;
 
@@ -34,7 +35,7 @@ pub fn init(mmap: *const MultibootTagMmap, mmap_size: usize)
 	alloc.read_grub_mmap(mmap, mmap_size);
 
 	let page_directory_addr = alloc.request_free_page(true);
-	let mut pt_manager = pagetable::Manager::new(page_directory_addr);
+	let mut pt_manager = pagetable::Manager::new(page_directory_addr, PDE_RW);
 
 	id_map(&mut pt_manager);
 	alloc.print_memusage(1);
@@ -46,7 +47,7 @@ pub fn init(mmap: *const MultibootTagMmap, mmap_size: usize)
 	}
 	let page = alloc.request_free_page(false);
 	crate::logln!("requested page userspace: {:#0X}", page);
-	pt_manager.memory_map(0x150000, page, 3);
+	pt_manager.memory_map(0x150000, page);
 }
 
 fn id_map(pt_manager: &mut pagetable::Manager)
@@ -57,7 +58,7 @@ fn id_map(pt_manager: &mut pagetable::Manager)
 
 	for i in 0..memory_start / PAGE_SIZE
 	{
-		pt_manager.memory_map(i * PAGE_SIZE, i * PAGE_SIZE, 3);
+		pt_manager.memory_map(i * PAGE_SIZE, i * PAGE_SIZE);
 		alloc.lock_page(i);
 	}
 }

src/memory/pagetable.rs

@@ -30,20 +30,22 @@ pub mod flags
 pub struct Manager
 {
 	pub page_directory: &'static mut [page::DirectoryEntry],
-	paging_enabled: bool
+	paging_enabled: bool,
+	flags: usize,
 }
 
 impl Manager
 {
-	pub fn new(addr: usize) -> Manager
+	pub fn new(addr: usize, flags: usize) -> Manager
 	{
 		unsafe
 		{
 			libc::memset(addr as *mut c_void, 0, PAGE_SIZE);
 			let manager = Manager
 			{
 				page_directory: core::slice::from_raw_parts_mut(addr as *mut page::DirectoryEntry, 1024),
-				paging_enabled: false
+				paging_enabled: false,
+				flags: flags,
 			};
 			manager.page_directory[1023].set_addr(addr as u32);
 			manager.page_directory[1023].set_rw(true);
@@ -63,7 +65,7 @@ impl Manager
 		self.page_directory = core::slice::from_raw_parts_mut(0xffff_f000 as *mut page::DirectoryEntry, 1024)
 	}
 
-	fn create_page_directory_entry(&mut self, index: usize, flags: usize)
+	fn create_page_directory_entry(&mut self, index: usize)
 	{
 		let page_directory_entry = &mut self.page_directory[index];
 
@@ -72,7 +74,7 @@ impl Manager
 			let alloc = pageframe::Allocator::shared();
 			page_directory_entry.reset();
 			page_directory_entry.set_addr(alloc.request_free_page(true) as u32);
-			page_directory_entry.value |= flags as u32 & 0xFFF;
+			page_directory_entry.value |= self.flags as u32 & 0xFFF;
 			page_directory_entry.set_present(true);
 			unsafe
 			{
@@ -81,7 +83,7 @@ impl Manager
 		}
 	}
 
-	fn create_page_table_entry(&mut self, page_directory_index: usize, page_table_index: usize, physical_address: usize, flags: usize)
+	fn create_page_table_entry(&mut self, page_directory_index: usize, page_table_index: usize, physical_address: usize)
 	{
 		let page_table = unsafe
 		{
@@ -92,16 +94,16 @@ impl Manager
 		{
 			page_table_entry.reset();
 			page_table_entry.set_addr(physical_address as u32);
-			page_table_entry.value |= flags as u32 & 0xFFF;
+			page_table_entry.value |= self.flags as u32 & 0xFFF;
 			page_table_entry.set_present(true);
 		}
 	}
 
-	pub fn memory_map(&mut self, v_addr: usize, phys_addr: usize, flags: usize)
+	pub fn memory_map(&mut self, v_addr: usize, phys_addr: usize)
 	{
 		let (pdi, pti): (usize, usize) = page_map_indexer(v_addr);
-		self.create_page_directory_entry(pdi, flags);
-		self.create_page_table_entry(pdi, pti, phys_addr, flags);
+		self.create_page_directory_entry(pdi);
+		self.create_page_table_entry(pdi, pti, phys_addr);
 	}
 
 	fn address(&self, page_directory_index: usize) -> u32